Stabilized dispersion of behenyl alcohol

ABSTRACT

IR 6 ( Cosmetics, Toiletry and Fragrance Association, Inc., 7   th  ed. 1997).  Viscosities are measured using Brookfield viscometers  (1,000-20,000 cps, Spindle No. 5, 20 rpm, 60 second run, 25 degrees C.) unless otherwise indicated. 967-00—IR # 6967-00-1-A low viscosity, stable dispersion of behenyl alcohol comprising: (a) 10-40 weight % on an actives basis of behenyl alcohol; (b) 1.0-8.0 weight % of an anionic surfactant selected from the group consisting of sodium lauryl ether sulfate, sodium lauryl sulfate, magnesium lauryl ether sulfate, magnesium lauryl sulfate, calcium lauryl ether sulfate, calcium lauryl sulfate, ammonium lauryl ether sulfate, and ammonium lauryl sulfate; and (c) 1.0-3.0 weight % (on an actives basis) of a betaine selected from the group consisting of C12-18 amidopropylbetaine; wherein the dispersion has a stability of at least 3 months at a temperature of 49 degrees C., a viscosity in the range of 1,000-20,000 centipoise, and no more than 0.2 weight % of cationic material.

BACKGROUND OF INVENTION

[0001] 1. Field of the Invention

[0002] This invention relates to ways of stabilizing dispersions ofbehenyl alcohol, to create improved pearlizing compositions which can bestable at room temperature.

[0003] 2. Background of the Invention

[0004] The stabilization and use of behenyl alcohol is described in avariety of references.

[0005] U.S. Pat. No. 4,892,728 to Kawa et al describes pumpable cationicfatty alcohol dispersion with a low content of cationic dispersant. Thedispersion is made with 0.01-1 weight % of a cationic surfactantcontaining a quaternary ammonium, pyridinium or imidazolinium group anda linear C8-22 alkyl or 2-hydroxyalkyl group.

[0006] U.S. Pat. No. 4,883,660 to Blackman et al describes gel bases forpharmaceutical compositions comprising behenyl alcohol and a glycol orselected ethoxylated solvent.

[0007] U.S. Pat. No. 5,100,657 to Ansheer-Jackson et al describes hairconditioning compositions which provide cleaner hair than others basedon quaternary ammonium compounds and lipid materials. The primarythickening agent is a nonionic long chain alkylated cellulose ether. Afatty alcohol such as behenyl alcohol is used as a conditioning agent.

[0008] U.S. Pat. No. 5,510,100 to Picard et al describes an oil-in-wateremulsion containing an auto-emulsifiable composition based on a fattyalcohol and on an alkyl polyoside and a co-emulsifying agent.

[0009] U.S. Pat. No. 5,827,920 to Wanatabe et al describes asurfactant-free emulsion comprising a higher alcohol which is a solid atroom temperature, an acrylic acid-methacrylic acid alkyl copolymer and asilicone oil.

[0010] U.S. Pat. No. 5,948,416 to Wagner et al describes stable topicalcompositions comprising a stable, hydrophobic, structuring agent (whichcan include behenyl alcohol), and a hydrophilic surfactant.

[0011] U.S. Pat. No. 5,973,066 to Sakuta et al describes an oil-in-wateraqueous organopolysiloxane emulsion comprising a quaternary ammoniumchloride having 1 or 2 stearyl or behenyl groups.

[0012] U.S. Pat. No. 6,274,130 to Murray et al describes a rinse offconditioning product for hair comprising a cationic surfactant, aselected emulsion polymerized dimethiconol nonionic conditioningpolymer, which composition can optionally include behenyl alcohol.

[0013] U.S. Pat. No. 6,419,946 to Sonneville et al describes ananoemulsion based on mixed esters of a fatty acid or fatty alcohol, ofa carboxylic acid and of a glycerol.

[0014] Behenyl alcohol has seen a variety of uses in personal careproducts, particularly for hair care. It is an object of the inventionto provide stabilized forms of behenyl alcohol which are useful aspearlizing agents and which are easier to use than conventional types ofbehenyl alcohol compositions.

SUMMARY OF INVENTION

[0015] A low viscosity, stable dispersion of behenyl alcoholcomprising:(a) from about 10 to about 40 weight % on an actives basis(preferably 20-25%) of behenyl alcohol;(b) from about 1.0 to about 8.0weight % (preferably 1-5%) of an anionic surfactant selected from thegroup consisting of sodium lauryl ether sulfate, sodium lauryl sulfate,magnesium lauryl ether sulfate, magnesium lauryl sulfate, calcium laurylether sulfate, calcium lauryl sulfate (best for avoiding viscosityproblems), ammonium lauryl ether sulfate, and ammonium laurylsulfate;(c) from about 1.0 to about 3.0 weight % (on an actives basis)of a betaine selected from the group consisting of C12-18amidopropylbetaine (for example, cocamidopropyl betaine); (d) optionallyfrom about 0.3 to about 5.0 weight % of a C12-C20 straight chain oriso-branched alcohol having 2-20 (particularly 2-10) moles ofethoxylation (for example, Isosteareth-2, lsosteareth-4, Isosteareth-10,Laureth 2-20, and especially Laureth-2, Laureth-4 and Laureth-10) (withhigher amounts of ethoxylation being used for the longer carbon chains);and(e) optionally a cationic material having less than or equal to 22carbons (for example, a cationic material such as a C8-22 alkyl ammoniumchloride, preferably one selected from the group consisting of cetyltrimethyl ammonium chloride, (also called cetrimonium chloride) andcocotrimethylammonium chloride); wherein the dispersion:(a1) has astability of at least 3 months at a temperature of 49 degrees C.;(b1)has a viscosity in the range of 1,000-20,000 centipoise (“cps”) (forexample, 1,000-20,000 cps, particularly 1,000-15,000 cps, and, moreparticularly, 1,000 cps-8,000 cps); and(c1) is limited to less than 0.2weight % of total cationic material.

[0016] The invention also comprises a method for (A) combining theingredients listed above;(B) melting and mixing the set of ingredientsusing a temperature in the range of about 80 to about 85 degrees C. tocreate a combined material;(C) stirring and homogenizing the combinedmaterial at a temperature in the range of about 80 to about 85 degreesC. for at least about an hour; (D) cooling the combined material down toa temperature in the range of about 20 to about 25 degrees C. at acooling rate in the range of about 0.05-0.4 degrees C./minute,preferably 0.15-0.3 and, most preferably, at a rate of 0.2-0.25 degreesC./minute; and(E) holding the combined material at the temperature ofabout 20 to about 25 degrees C. for at least 2 hours.

DETAILED DESCRIPTION

[0017] The dispersions of the invention are shear thinning. Since thedispersion can increase in viscosity during storage, it is preferred toinitially make the dispersion at the lower range of viscosity such as inthe range of 1,000-5,000 cps.

[0018] By “stable” is meant that the dispersion is judged by visualobservance as giving 0% separation even at temperatures in the range of49 degrees C.for the 3 month time period described. It has been foundthat at least 1% of the anionic surfactant and at least 1% of thebetaine are needed in order to get the superior stability described forthe invention.

[0019] It is preferred to include Isosteareth-2 if a hair conditioningproduct is to be made since it contributes to the conditioning effect ofthe final hair care composition.

[0020] The behenyl alcohols included in this invention can includenatural as well as synthetically made alcohol. For natural alcohol, itis understood that a distribution of carbon lengths is included. Onepreferred type of behenyl alcohol useful for this invention is a 72-80%material sold under the tradenames Lanette 22, Stenol 1822 A, Stenol1822-80, and Lanette 22-80.

[0021] The alcohols are used in this invention to obtain a pearlizingeffect (such as in hair care products such as shampoos, conditioners andcombination products) and processability.

[0022] The use of dispersions of alcohols (especially behenyl alcohol)is helpful in keeping process costs down since the dispersion allowsstable hair car products to be made with a cold process.

[0023] Viscosity is related to particle size control; during themanufacturing process the dispersion must be cooled down to at least 25,most preferably 20 degrees C. and kept at this temperature of 20-25degrees C. for at least for 2 hours to get a good viscosity result.

[0024] The ingredients described above are commercially available.

[0025] TABLE A shows the impact on viscosity of final temperature forcooling down.

[0026] Procedure: Melt and/or mix up all the ingredients listed for thespecific Example. Heat the mixture up to a temperature in the range of80-85 degrees C. Stir/homogenize the material for 1 hour and then startto cool down with a cooling rate of 0.2-0.25 degrees C./min. Viscositywas measured 24 hours after manufacturing/finishing the compound withBrookfield equipment, RVT, 25 C., Spindle 5, 20 rpm. TABLE A IngredientEx. 1A Ex. 2A Ex. 3A Water QS QS QS Sodium Lauryl 2EO 6.0 6.0 6.0Sulfate Cocamidopropyl 1.0 1.0 1.0 betaine Laureth-4 1 1 1 Behenylalcohol 25.0 25.0 25.0

[0027] Cooled-down to 30° C. 25,000 mpas Cooled down to 25° C. 15,000mpascooled down to 25° C. and 5000 mPascals kept 2 hours at 25degrees C.It is preferred to have the combination of Isosteareth-2 and Betaine.Also, when fatty alcohol ethoxylates are ethoxylates are used, themaximum amount should preferably be kept to 2%, for example, between1-2%,

EXAMPLES

[0028] The following Examples are offered as illustrative of theinvention and are not to be construed as limitations thereon. In theExamples and elsewhere in the description of the invention, chemicalsymbols and terminology have their usual and customary meanings. In theExamples as elsewhere in this application values for viscosity,molecular weights and degree of ethoxylation or propoxylation areaverages. Temperatures are in degrees C. unless otherwise indicated. Asis true for the rest of the application as well, the amounts of thecomponents are in weight percents based on the standard described; if noother standard is described then the total weight of the composition isto be inferred. Various names of chemical components include thoselisted in the CTFA International Cosmetic Ingredient Dictionary

Example A

[0029] General Method To the main mixing vessel is added water and theanionic surfactant (such as sodium laureth sulfate). The mixture isstirred with heating to a temperature of 80-85 degrees C. Then the pH isadjusted to pH 7-8. After this adjustment the alkylamidopropylbetaineand the nonionic surfactant are added while maintaining the temperatureis at 80-85 degrees C. When addition of the surfactant is completed thebehenyl alcohol is added in molten liquid (such as Lanette-22 (72-80%)or slowly in solid state so that the temperature is maintained at 80-85degrees C. The contents of the mixing vessel are stirred for at least45-60 minutes at 80 to 85 degrees C. Next the vessel is cooled down at acooling rate of 0.05-0.4 degrees C./minute, preferably 0.1 5-0.3 and,most preferably, at a rate of 0.2-0.25 degrees C./min. After the mixtureis cooled to about 20-25 degrees C. the specifications are checked. Themixture is then stirred for another 1-2 hours at 20-25 degrees C.Viscosity may be measured, if desired, using the equipment andconditions described above.

Examples 1-15

[0030] The General Method described in Example A may be used to make 5kg size batches using the types and amounts of ingredients listed inTables B-D. Examples 1-6 are comparative examples to show formulationsoutside of the invention. TABLE B Single Surfactant Systems IngredientEx. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Ex. 6 Water QS QS QS QS QS QS SodiumLauryl 2EO 1.0 8.0 0 0 0 0 Sulfate Cocamidopropyl 0 0 2.0 4.0 0 0betaine Cetrimonium chloride 0 0 0 0 0.80 5.0 Behenyl alcohol 10.0 40.010.0 30.0 10.0 40.0 Total 100 100 100 100 100 100

[0031] Viscosity measurements were:Example 1: non-homogeneous, lumpy,100 mpasExample 2: sticky paste, lumpy,>100000 mpasExample 3:non-homogeneous, lumpy, 100 mpasExample 4: non-homogeneous, lumpy, 200mpasExample 5: non-homogeneous, lumpy, 1000 mpasExample 6: paste, lumpythick, white cream>100000 mpas TABLE C Multiple Surfactant Systems WithIsosteareth-2 Ingredient Ex 7 Ex 8 Ex 9 Ex 13 Ex 14 Water QS QS QS QS QSSodium Pareth 2EO Sulfate 0 0 0 0 4.0 Sodium Lauryl 2EO Sulfate 2.0 4.01.0 2.5 0 Cocamidopropyl betaine 1.0 2.0 1.0 1.0 0 Cetrimonium chloride0 0 0.5 0.2 0 Isosteareth-2 2.0 1.0 0.5 0.5 2.0 Behenyl alcohol 25.025.0 25.0 25.0 25.0 Laureth 1-10 0 0 0 1.0 0 Total 100 100 100 100 100Stability stable stable unstable borderline unstable

[0032] TABLE D Multiple Surfactant Systems Without Isosteareth-2Ingredient Ex 10 Ex 11 Ex 12 Ex 15 Water QS QS QS QS Sodium Lauryl 2EOSulfate 4.0 0.5 0.5 3.0 Cocamidopropyl betaine 1.0 0.5 0.25 3.0 Behenylalcohol 25.0 15.0 25.0 25.0 Laureth 1-10 2.0 1.0 4.0 0 Total 100 100 100100 Stability stable unstable unstable stable

What is claimed is:
 1. A low viscosity, stable dispersion of behenylalcohol comprising: about 10-40 weight % on an actives basis of behenylalcohol; about 1.00-8.0 weight % of an anionic surfactant selected fromthe group consisting of sodium lauryl ether sulfate, sodium laurylsulfate, magnesium lauryl ether sulfate, magnesium lauryl sulfate,calcium lauryl ether sulfate, calcium lauryl sulfate, ammonium laurylether sulfate, and ammonium lauryl sulfate; about 1.0-3.0 weight % (onan actives basis) of a betaine selected from the group consisting ofC12-18 amidopropylbetaines; optionally about 0.3-5.0 weight % of aC12-C20 straight chain or iso-branched alcohol having 2-20 moles ofethoxylation; optionally a cationic material having less than or equalto 22 carbons; wherein the dispersion: has a stability of at least 3months at a temperature of 49 degrees C.; has a viscosity in the rangeof 1,000-20,000 centipoise; and is limited to less than 0.2 weight % oftotal cationic material.
 2. A low viscosity, stable dispersion ofbehenyl alcohol according to claim 1 comprising about 20 to 25% ofbehenyl alcohol; and about 1 to 5% of the anionic surfactant.
 3. A lowviscosity, stable dispersion of behenyl alcohol according to claim 1having a viscosity in the range of 1,000-15,000 cps.
 4. A low viscosity,stable dispersion of behenyl alcohol according to claim 1 having aviscosity in the range of 1,000-8,000 cps.
 5. A low viscosity, stabledispersion of behenyl alcohol according to claim 1 wherein the betaineis cocoamidopropyl betaine.
 6. A low viscosity, stable dispersion ofbehenyl alcohol according to claim 1 wherein the anionic surfactant iscalcium lauryl sulfate.
 7. A low viscosity, stable dispersion of behenylalcohol according to claim 1 wherein the C12-C20 straight chain oriso-branched alcohol having 2-20 moles of ethoxylation is selected fromthe group consisting of Isosteareth-2, lsosteareth-4, Isosteareth-10,and Laureth 2-20.
 8. A process for making a stable dispersion of behenylalcohol wherein the dispersion has a stability of at least 3 months at atemperature of 49 degrees C.; a viscosity in the range of 1,000-20,000;and no more than 0.2 weight % of a cationic material, wherein the methodcomprises: combining a set of ingredients comprising: 10-40 weight % onan actives basis of behenyl alcohol; 1.0-8.0 weight % of an anionicsurfactant selected from the group consisting of sodium lauryl ethersulfate, sodium lauryl sulfate, magnesium lauryl ether sulfate,magnesium lauryl sulfate, calcium lauryl ether sulfate, calcium laurylsulfate, ammonium lauryl ether sulfate, and ammonium lauryl sulfate;1.0-3.0 weight % (on an actives basis) of a betaine selected from thegroup consisting of C12-18 amidopropylbetaines; and optionally 0.3-5.0weight % of a C12-C20 straight chain or iso-branched alcohol having 2-20moles of ethoxylation; melting and mixing the set of ingredients using atemperature in the range of 80-85 degrees C. to create a combinedmaterial; stirring and homogenizing the combined material at atemperature in the range of 80-85 degrees C. for at least an hour;cooling the combined material down to a temperature in the range of20-25 degrees C. at a cooling rate in the range of 0.05-0.4 degreesC./minute; and holding the combined material at the temperature of 20-25degrees C. for at least 2 hours.